Added dedicated readimage.h include file
Added subimage.c module and subimage.h include file, in charge of creating and managing sub-images.
Removed manobjlist.c and moved content to deblend.c.
More code refactoring (including readimage header and neurro modules), and removal of global function definitions.
Added new wcs_rawtoraw() function in fitswcs module to compute local reprojection offsets and Jacobians.
Completed multi-grid support, including background subtraction (not yet fully optimized)
Fixed crashes with FILTER set to Y.
Implemented multi-grid support in winpos module (not yet fully accurate, needs testing) and photom_auto (not functional yet).
Pushed version number to 3.0a5